Mobile Home

[GG]

I have a mobile home that needs its service connected. The service disconnect is 25' from the MH. The 200A MBP panel in the MH has the EGC bus and neutral bus seperated, a bonding conductor going to the frame of the MH, and a CWG. At the service disco. outside there is a ground rod. My question is does the MH also need a ground rod or are the CWG and frame all the grounding/bonding that is needed?

 

[augie47]

Re: Mobile Home

IMHO, ground rod (s) at the service disconnect (25' away), EGC to mobile.

 

[GG]

Re: Mobile Home

I guess if the MH is struck by lightning the path it could take is the CWG and the EGC tied to the ECG going to the ground rod back at the service disconnect outside.

 

[petersonra]

Re: Mobile Home

something about having the GE 25' away bothers me.

 

[jimwalker]

Re: Mobile Home

Actually it has several ground rods,they are called anchors

 

[benaround]

Re: Mobile Home

GC,

Have you had a chance to review art. 550 .

frank

 

[GG]

Re: Mobile Home

Hi Frank, I have read 550 a few times now. I have come to the conclusion that I drive a ground rod at the service disco, and bond the GEC and neutral. Then I run a 4 wire feeder to the MH panel (2 hots, 1 neutral, 1 EGC) and keep the EGC bus and neutral bus separate. I check to make sure the CWG and frame bond were installed by the manufacturer, and then Im done. I havent done a MH in over 2 years, and I just wanted to make sure Im doing my install to code. Does the install I described sound right to you? Thanks.

 

[iwire]

Re: Mobile Home

Add a grounding electrode at the MH per 250.32.

 

[benaround]

Re: Mobile Home

GC,

Last time I did this a 50a supply cord was the required method !!!

As 'Iwire' has already mentioned this MH is a seperate building from the struture that the main disconnecting means is secured to, thus a GEC at the MH connected to the EGC is required.

Everything else you got covered.

frank

 

[haskindm]

Re: Mobile Home

550.32 states that the disconnecting means (service) may be located up to 9.0 meters (30 feet) from the Mobile Home. In this case the distance is 25 feet so that meets this requirement. The grounding electrode is required at the disconnect. There is no mention of requiring a second electrode at the mobile home. If the disconnect was further than 30 feet from the mobile home another disconnect would be required and that disconnect would require a grounding electrode. But it appears in this case the installation is fine.

 

[benaround]

Re: Mobile Home

haskindm,

Even if this was a normal single family,with the main disc. on remote pole a GES is still required at the home.250.32 (d)

frank

 

[jimwalker]

Re: Mobile Home

I have only hooked up 2 mobiles in my life.Both were permited and inspected.Neither had that extra ground rod.
But after reading all this i must agree they are 2 seperate structures so 2 rods are needed.So why did i pass ?

[ August 12, 2005, 08:32 PM: Message edited by: jimwalker ]

 

[augie47]

Re: Mobile Home

Quit confusing me with facts! My mind is made up!
550 says our service disconnecting means shall not be mounted on the mobile home. Often is is adjacent (2-5') with a Grounding Electrode connected to that disconnecting means....
if we move it to the 30' allowable point, what has changed?
a post/pole with a meter and disconnect is not a seperature structure to me.
Wheres a code panel memeber when you need onme ?

 

[iwire]

Re: Mobile Home

Originally posted by augie47:
a post/pole with a meter and disconnect is not a seperature structure to me.

But it is to the NEC.

Article 100

Structure. That which is built or constructed.

Unless that post/pole with a meter and disconnect grew from a seed that fell from a tree it is indeed a structure.

But that is irrelevant anyway, at this 'post/pole with a meter and disconnect' you have a service disconnect which requires grounding electrode.

The MH is without a doubt a structure and also requires grounding electrodes.

 

[augie47]

Re: Mobile Home

jeeze..sometimes i hate that book even though i earn a livinbg by it...
thanks for correcting me iwire

still, i ponder, if this pole "structure" is 2' from that mobile home structure, and there is a grounding electrode and gec to the meter or disconnect on the pole STRUCTURE, how many inspectors require a second GE or GEC on the mobile home?

 

[iwire]

Re: Mobile Home

Originally posted by augie47:
still, i ponder, if this pole "structure" is 2' from that mobile home structure, and there is a grounding electrode and gec to the meter or disconnect on the pole STRUCTURE, how many inspectors require a second GE or GEC on the mobile home?

What difference does it make if the inspectors require it?

If it is a code you are required to put it in, if you don't put it in and the 'S' hits the fan it will be you on the hook for not installing it.

I have no idea what the extra GEC will do for you if the structures are only two feet apart but keep in mind that the code is written to cover all installations and many times the structures are further apart than 2'

I doubt a ground rod will do much at all except meet the NEC requirements.

Include it in your price and make money installing it.

 

[augie47]

Re: Mobile Home

perhaps I should re-word that....
for the record: doesn't make a dime one way or the other to me...I am an inspector...one who tries very hard to enforce the CODE, not what I wish, not what I'd like to see personally, but the CODE...but, I read the ROPs etc and try to take intent in to the picture...perhaps thats wrong, but I sure don't think the intent of 250-32 is to require a second grouding electrode 2'on a MH with a GE and GEC at the serice pole 2' away.
My comment was more to the effect that I wonder how many inspectors interpret the code this way.

 

[iwire]

Re: Mobile Home

Ahh I see now.

Well here is how I see it.

Whenever any structure is fed the NEC requires grounding electrodes at that structure.

In the case of one structure fed from another 99% of the time these structures will be much further apart then 2'

Currently there is no NEC exception for two structures that are very close together.

Without an exception I do not see how you can ignore the requirement in 250.32.

If you feel a post, meter, and service disconnect is not a structure than I assume you would not require any GECs at a temp power pole?

This is just my opinion and you know what they say about opinions....

 

[roger]

Re: Mobile Home

Aha, but there is nothing stopping us from using the same GE or GES for multiple structures, even if a lengthy GEC is needed.


Roger

 

[iwire]

Re: Mobile Home

Originally posted by roger:
Aha, but there is nothing stopping us from using the same GE or GES for multiple structures, even if a lengthy GEC is needed.


Roger

I certainly agree with you on that.